Twitter beginners need to understand the rules of etiquette for the service. So before you stick a foot measuring 140-characters-or-less in your mouth, check out our advice on how to follow and un-follow, share politely, direct message appropriately, and more.

In our beginner's guide about how to get started on Twitter, we examined the basics of the social networking service that allows you to share short messages (140 characters or less) with friends, family and colleagues. But like any social network, the Twitter community has its own set of unwritten guidelines — or etiquette — that dictates good (or bad) behavior on the service. Some people call it Twittequette.

We call our tips guidelines, instead of rules, because Twitter was designed to be a very open forum. Some people might feel differently about what constitutes good Twitter behavior, depending on what they hope to get out of the service or their networking philosophies in general.

But based on interviews we did with social media and career experts who have seen people try to balance their personal and business lives on Twitter, we worked up five dos and don'ts for the average Twitter user, from deciding whose Twitter messages (known as "tweets") to follow or what content to share without jeopardizing what matters most in your professional and personal lives.

1. How to Follow and Un-Follow People

Even social networking experts share different philosophies on how to deal with "followers" — the people on Twitter who subscribe to your tweets. Some people believe that if someone follows you, it's impolite not to follow that person back. (Under Twitter's default settings, you'll generally be notified by e-mail when someone decides to follow you, and you'll be provided with a link to the person's Twitter profile, where you can choose to follow the person back and receive his or her tweets.)

But especially if you're just starting off on Twitter, you shouldn't feel obligated to follow all people back, even if you worry they'll think it's rude of you, our experts say. Instead, you should follow people who share your interests or whose tweets you find meaningful or compelling.

"You should only follow people who you trust, you think are interesting, or that you learn from," says Jeremiah Owyang (@jowyang), a senior Forrester analyst who researches social technologies and keeps a blog on Web strategy.

It's possible you'll offend some people, but ultimately it's harder to maximize the value of Twitter early on if you're Twitter homepage is flooded with tweets unrelated to your field or tweets that don't make any sense to you, Owyang says.

At the same time, don't be afraid to take some risks and follow someone outside your immediate circle, says Stowe Boyd (@stoweboyd), a social media consultant who writes the /message blog.

"It's like wandering around at a cocktail party," Boyd says. "You don't just want to hang out with people you only know well. Pick ten of your friends who are using Twitter, follow them, and then pick ten of their friends and follow them. You can always drop people and add new ones."

Similarly, don't be offended if someone un-follows you or chooses not to follow you back. Boyd says he'll stop following someone, for instance, who keeps tweeting things for a few days (such as from a conference) that don't capture his interest. He'll begin following the person again after that event is over.

Unlike a cocktail party, however, where the attendees aren't journalists with recorders and notepads, Twitter is a publishing medium where your messages will ring with finality to a lot of people. Because a tweet must be 140 characters or less, context can be easily misunderstood. Also, don't assume that people who are your immediate followers will only see your tweets. A tweet can be picked up publicly by Google or Twitter's search tool.

"It's open social discourse," Boyd says. "As a result, to some extent, some of what you say is going to be available for the public to see."

One complaint often voiced in the Twitter community concerns people who tweet too frequently, dominating users' homepages with their messages. Again, you can avoid this by examining a person's profile page before you sign up to follow him. If you don't want to follow the person, don't get mad at them for tweeting in volume .

Also, if you're just getting started, it's not recommended that you start following the more celebrity accounts or power Twitter users who tweet a lot, says says Laura Fitton (@pistachio), who runs Pistachio Consulting, which advices businesses on how to utilize Twitter.
"They'll dominate your stream," Fitton says, whose Pistachio account has more than 18,000 followers. "I say follow me on RSS instead, which is an option on Twitter."

2. Be Up Front About Your Twitter Aspirations

As the divide between our consumer and professional lives blurs at the hands of social technologies, the content of your tweets can take on a whole new meaning, especially if you work at a traditional corporation that doesn't acknowledge this reality.

As such, you might want to make it clear who you represent and why you're on Twitter. Some people put messages on their Twitter background (which can be customized under the "settings" tab), noting that the opinions expressed in their tweets don't necessarily reflect those of their employers. They also might provide a link that explains with greater detail why they're on Twitter. While this can allow you some leeway, it doesn't necessarily mean your employer or your followers won't call you out on some tweets.

"There's a real difficulty there," Boyd says. "For people who are employed by companies, to some extent, they're always a representative of the company. It's almost impossible to divorce yourself from that. They need to figure out where they can draw line, and for some people where that line is is different."

In the end, the more up front you are in your profile description about who you represent and what you plan to talk about, the more you'll allow yourself some cover, says Kirsten Dixson (
@kirstendixson
), a reputation management and online identity expert. But that also means you shouldn't get upset with people if they tweet something that's in line with their stated Twitter goals.

"They might have things that are off-putting, that are overtly religious or political and not in your own views," she says. "But if they're up front about that, they've been fair."

3. Be Personal (to a point)

While you should heed the advice of the aforementioned section, you also shouldn't be afraid to be personal in your Twitter account. Most people wouldn't join Twitter to be spun by your corporate boilerplate statement or marketed to in traditional fashions. For individuals, Twitter can be a very personal medium, and that's not a bad thing for business people.

Twitter can humanize you in the eyes of your followers (who might want to do business with you in the future as a result of that human interaction).

"Work relationships have always been infused with some aspects of the personal, and Twitter is no different," Fitton says. "If you walked around the office and talked to people sitting in the cubes, people have different personality styles and quirks."

Your personal tweets should have meaning to your audience. Tweet about issues that are fairly universal to your list of followers and that will make them feel welcome to reply to with their own comments.

"People's Twitter streams are uninteresting if they're just declarative sentences like 'I'm going to the movies' or 'it's gray outside,'" Boyd says. "It's better if it's something that people might feel interested in replying to."